药物干预幼大鼠缺氧缺血性脑损伤与p53蛋白表达的研究

Expression of p53 protein in the infant rats with hypoxic-ischemia brain damage

目的通过检测缺氧缺血性脑损伤(HIBD)幼大鼠脑组织中p53蛋白的表达和一氧化氮(NO)、一氧化氮合酶(NOS)、超氧化物歧化酶(SOD)含量,探讨HIBD的发病机制;了解神经节苷酯(GM1)和胞二磷胆碱干预对HIBD的影响。方法80只Wistar幼大鼠随机分四组;对照组、缺氧缺血组、GM1组、胞二磷胆碱组。17日龄制作HIBD模型,24 h后处死检测脑组织中p53蛋白的表达和NO、NOS、SOD含量及组织形态学的变化。结果缺氧缺血组NO、NOS含量高于其他三组(P<0.05);缺氧缺血组与胞二磷胆碱组SOD含量低于对照组和GM1组(P<0.05);缺氧缺血组p53蛋白表达高于其他三组(P<0.01),GM1和胞二磷胆碱组p53蛋白表达高于对照组(P<0.01);组织形态学改变显示,缺氧缺血组变性、坏死严重,GM1组与胞二磷胆碱组次之,对照组正常。结论NO和自由基引起的组织损伤可能诱导p53蛋白表达导致HIBD。GM1和胞二磷胆碱能改善脑组织NO、NOS、SOD含量和p53的表达,提示GM1和胞二磷胆碱对HIBD有一定的保护作用。

Objectives To explore how expression of p53 protein, nitric oxide （NO） level, nitric oxide synthetase （NOS）, superoxide dismutase （SOD） change in infant rats with hypoxic-ischemia brain damage （HIBD）, and the influence of monosialoganglioside （GMI） and cytidine diphosphate choline （CDPC） on HIBD. Methods The models of infant-rats with HIBD were established by means of hypoxic-ischemia as described elsewhere. Eighty （80） infant-rats were randomly divided into four groups. 1. Control group 2. HIBD group 3. Monosialoganglioside （GM1） group （GM1： 30 mg/kg each abdominal injection, five injections after hypoxic-ischemia） . 4. CDPC group （citicoline sodium： 40 mg/kg each abdominal injection, five injections after hypoxic-ischemia） . The infant rats were killed 24 h after hypoxic-ischemia, NO, NOS, SOD were measured and changes of p53 protein expression were then determined by immunohistochemistry in the brain and histopathological examination were also performed. Results 1. There were significant increase of NO, NOS in HIBD group, compared with other three groups （all P 〈 0.05） . SOD of both HIBD and CDPC groups was lower than that of control and GMI groups （P 〈 0.05）. 2. Expression of p53 protein was significantly higher in HIBD group than that of GMI group and CDPC group （P 〈 0.05）. 3. Disarrangement of cortical cell structure and swollen of nucleus and interstitial were found under light microscopy in HIBD group, while morphological changes were milder in GM1 and CDPC groups. Conclusions NO and free radicals are significant to the pathogenesis of hypoxic-ischemia brain damage and induce the expression of p53 protein. GM1 and citicoline sodium play a role in protecting brain from hypoxic-ischemia damage.